In the field of roofing, and especially in the field of installing metal roofing, it is well known that safety issues are of great concern. Metal roof systems are well known in the art, as are their methods of installation. Each different roof system requires particular steps in connecting individual roofing panels to each other and to roof trusses. However, all metal roof systems have many basic similarities. For example, it is well known that a metal roof construction includes a number of roof trusses disposed in parallel fashion, and at progressively increasing elevations to define a slope. The slope may be defined either from one side of the roof to the other, or from both sides of the roof toward the center, depending upon the particular structure. Roof trusses in conventional roofs may be any conventional material and configuration.
Roof panels are then laid across the roof trusses in the direction of the slope, and at a right angle with respect to the direction of the roof trusses. The individual roof panels are placed from the bottom of the slope to the top, with each successive panel overlapping the last in order to prevent moisture from seeping between. A sealant may be used to further effect a moisture-tight seal. Adjacent roof panels are typically provided with an engagement mechanism to secure the panels together in a sealed disposition After the roof panels are positioned as desired, they are fastened to the roof trusses. However, it is common to position a layer of insulation on top of the roof trusses prior to placing and securing the roof panels. Thus, after the insulation is in place, and before the roof panels are positioned, the insulation is merely laying on the roof trusses. Because there is typically no decking between the insulation and the roof trusses, the insulation provides no support for carrying a load.
Due to the placement of the insulation, there have been roof installers who have had a false sense of security in the insulation and, without thinking, have placed all of their weight on the insulation and have thus fallen through to the ground. If there is nothing between the insulation and the ground to break their fall, they will fall on what is typically a concrete floor, thus causing extensive physical damage, and in some cases, death. Accordingly, in an environment such as the installation of a metal roof in the manner described, safety precautions are required.
Other systems have been developed to assist in the installation of a metal roof as described. Typical of the art are those described in U.S. Pat. Nos. 5,551,203 and 5,561,959, both issued to R. J. Alderman, et al. As described by the assignee of these patents, Owens Corning, the system described in the '203 and '959 patents, marketed by Owens Corning as at the "Elaminator System", is designed to provide safety solutions for laminators and builders, as well as cost- and time-effective methods to improve thermal performance. The '203/'959 system includes a carriage which is urged along the purlins of the roof structure. A roll of insulation is mounted to the carriage and dispenses a substantially continuous sheet of blanket insulation material over the purlins as the carriage is progressively moved along the length of the purlins. A radiant barrier dispenser dispenses a layer of radiant barrier material over the dispensed blanket insulation material and a cross-wise layer of insulation is applied across the length of the purlins in a direction normal to the direction of application of the blanket insulation material. Thereafter, sheets of hard metal roofing material are attached to the purlins over the cross insulation to form the insulated roof structure. The radiant barrier material is configured to be received between the purlins, and cannot provide a load bearing surface. Specifically, the '203/'959 system does not provide for the safety of a roofer who may place his weight on the insulation layer, whether intentionally or by accident.
An improvement to the '203/'959 system is the "PERFECT R system marketed by CGI/Silvercote, Inc. The PERFECT R insulation system is provided for applying metal building insulation to pre-engineered buildings using a vapor retarder machine which attaches the facing to the top of the roof purlins, trusses or joists. The PERFECT R insulation system, as described by CGI/Silvercote, is designed to provide a cleaner appearance on the interior of metal buildings and to fiicilitate speed and ease during the installation of insulation, as compared to the '203/'959 system described above. The PERFECT R insulation system includes two tape dispensers that apply two-sided tape to the facing as the machines are manually advanced down the length of the building by a push rod. The machines simultaneously dispense and position the facing to a preset depth as they are moved. However, the PERFECT R insulation system does not include a means for supporting the weight of a worker on the insulation. Specifically, the system is described as providing a finished roof area from which to work, once the first roof panels are installed. Further, the PERFECT R insulation system, while claiming to provide a safer work environment, specifically disclaims the use thereof as a fall protection device. One device that is provided as a fall protection device is that disclosed by R. H. Van Auken, et. al., in U.S. Pat. No. 5,251,415. The '415 device is a nonmetallic mesh that is stretched across the entire area of the roof and secured at the periphery of the roof The mesh is placed loosely over the purlins in order to accommodate the placement of insulation. The mesh has sufficient strength to protect workers installing the roof in the event of an accident. However, the '415 device does not provide a surface on which the workers may walk during installation of the roof Further, due to the nature of the mesh material, while workers may be prevented from falling as a result of an accident, it does not prevent items such as tools, nails, and the like from falling through the openings in the mesh. Further, because the mesh is placed permanently as a component of the roof system, it may not be removed and reused, thus elevating the cost of installing the roof system.
Therefore, it is an object of this invention to provide a system for installing a metal roof system including an insulation layer placed over a series of purlins and under a metal deck while also providing a means for preventing workers from falling through the insulation. Another object of the present invention is to provide such a system whereby a working deck is provided for supporting insulation prior to securement of a section of metal decking.
Still another object of the present invention is to provide such a system whereby the working deck is moved along the purlins as the roof is being installed.
Yet another object of the present invention is to provide such a system whereby a material handling device is provided proximate the working deck such that time and energy dedicated to moving metal roofing materials is greatly reduced when compared to conventional alternatives.